Post-fledging migration of Sable Shearwaters (Ardenna carneipes) identifies the Solomon Sea as a potential conservation priority

Background
Juvenile survival is a critical yet poorly resolved demographic parameter in long-lived seabirds. Juvenile spatial ecology may differ remarkedly from adults in dispersal extent, habitat use, and migratory routing, as fledglings must independently and rapidly acquire foraging and navigational competency to migrate vast distances. This demographic-specific knowledge gap limits evidence-based marine spatial planning for vulnerable seabird populations. Here, we provide new data on the movement patterns of fledgling Sable Shearwaters Ardenna carneipes from Lord Howe Island, Australia to evaluate spatial ecology.

Methods
Sable Shearwaters were captured by hand from the colony surface immediately prior to fledgling. Solar-powered GPS loggers were attached to three central tail feathers in 2022 (n = 15) and 2024 (n = 15). All loggers were programmed to collect GPS locations (accuracy 5 m) at one-hour intervals.

Results
Juveniles departed Lord Howe Island rapidly, travelling on average 1000 (up to > 2,500) kilometres northward within the first two weeks post-fledgling and reaching the Solomon Sea by week 3, where they moved relatively short distances from east to west during the following weeks.

Conclusion
Across years, juvenile Sable Shearwaters showed consistency in migrating northward within the first two weeks of their migration, highlighting the Solomon Sea as a previously unrecognised and potentially critical stopover site for this species. By identifying this important habitat, our results provide a clear spatial focus for future conservation planning and the development of targeted area-based management measures.